nanog mailing list archives
Re: NTP Server
From: "Dobbins, Roland" <rdobbins () arbor net>
Date: Mon, 25 Oct 2010 02:09:59 +0000
On Oct 25, 2010, at 3:48 AM, Matthew Petach wrote:
NTP can potentially be used as a DoS vector by your upstream clocks, if you're not running your own.
+1 Also, if you experience a network partition event for any reason (DDoS attack, backhoe attack, et. al.) which disrupts communications between your network and the one(s) on the Internet where the public ntp servers you're using live, the accuracy of your time-hack becomes a concern just at the moment when you need it the most for combinatorial analysis of multiple forms of telemetry. And of course, time services for your infrastructure/services/apps ought to run across your DCN, anyways, which should be kept isolated from your production network (you don't want to rely upon proxies to enable something as critical as time service, IMHO). As Sean pointed out, all your routers from modern vendors are ntp-capable, and getting a couple of radio cards for servers to sync with WWVB isn't very expensive, assuming you can plug into an aerial which gets good reception: <http://www.nist.gov/pml/div688/grp40/wwvb.cfm> ----------------------------------------------------------------------- Roland Dobbins <rdobbins () arbor net> // <http://www.arbornetworks.com> Sell your computer and buy a guitar.
Current thread:
- Re: NTP Server, (continued)
- Re: NTP Server William F. Maton Sotomayor (Oct 26)
- Re: NTP Server John Kristoff (Oct 24)
- Re: NTP Server Joel Jaeggli (Oct 24)
- Re: NTP Server Sean Donelan (Oct 24)
- RE: NTP Server Brandon Kim (Oct 24)
- Re: NTP Server Cutler James R (Oct 24)
- RE: NTP Server Sean Donelan (Oct 24)
- Re: NTP Server John Kristoff (Oct 25)
- RE: NTP Server Brandon Kim (Oct 24)
- Re: NTP Server Matthew Petach (Oct 24)
- Re: NTP Server Marshall Eubanks (Oct 24)
- Re: NTP Server Dobbins, Roland (Oct 24)
- Re: NTP Server Jorge Amodio (Oct 24)
- Re: NTP Server Sean Donelan (Oct 24)
- RE: NTP Server Brandon Kim (Oct 24)
- Re: NTP Server Seth Mattinen (Oct 24)
- Re: NTP Server Marcus Reid (Oct 25)
- Re: NTP Server Seth Mattinen (Oct 24)
- Re: NTP Server Cutler James R (Oct 24)
- Re: NTP Server Sean Donelan (Oct 24)
- Re: NTP Server Martin Hotze (Oct 24)